roll wt_status_state into wt_status and populate in the collect phase

roll wt_status_state into wt_status and populate in the collect phase

Status variables were initialized in the collect phase and some
variables were later freed in the print functions.

A "struct wt_status" used to be sufficient for the output phase to
work.  It was designed to be filled in the collect phase and consumed
in the output phase, but over time some fields were added and output
phase started filling the fields.

A "struct wt_status_state" that was used in other codepaths turned out
to be useful in the "git status" output.  This is not tied to "struct
wt_status", so filling in the collect phase was not consistently
followed.

Move the status state structure variables into the status state
structure and populate them in the collect functions.

Create a new function to free the buffers that were being freed in the
print function.  Call this new function in commit.c where both the
collect and print functions were being called.

Based on a patch suggestion by Junio C Hamano. [1]

[1] https://public-inbox.org/git/xmqqr2i5ueg4.fsf@gitster-ct.c.googlers.com/

Signed-off-by: Stephen P. Smith <ischis2@cox.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>